Peter Antevy, MD, is an EMS medical director for the Coral Springs-Parkland Fire Department, Davie Fire Rescue, Southwest Ranches, and MCT Express in Florida, as well as medical director of pediatrics for Palm Beach County Fire Rescue. Antevy serves as medical director at the Coral Springs Institute of Public Safety and for Broward College’s EMS program and is a pediatric emergency medicine physician at Joe DiMaggio Children’s Hospital. He is founder and chief medical officer of Handtevy–Pediatric Emergency Standards, Inc.
Early in the COVID pandemic, aerosolized medications were removed from all of the ambulances across my EMS agencies. The sick, asthmatic or elderly patient suffering from COPD unfortunately could not receive the gold standard treatment of nebulized medications for fear of transmitting COVID-19 to the treating paramedics in the small confines of an ambulance. In order to protect the EMS professionals on the front lines, the decision was made by me that all nebulizations had to stop until further notice.
For similar safety reasons, the avoidance of nebulization treatments also became common in hospitals and urgent care centers.
Now, one year later, protocols across the country do not allow for aerosolized medications. With all of the media attention, even the lay person has become familiar with various aspects of the SARS-CoV-2 virus and its primary mechanisms of spread: respiratory droplets and aerosols. These have become household terms and now carry a negative connotation, but it’s not the aerosol itself that is concerning. It is the viruses that attach to them for a free ride and ultimately travel to the depths of the airways that pose a danger to others in the same confined space, such as paramedics in ambulances, or healthcare professionals in emergency departments and intensive care units across the country
It’s not the aerosol itself that is concerning. It is the viruses that attach to them
An aerosol is simply defined as a fine mist that is suspended in air. Due to their optimal delivery to the depths of the lungs, aerosolized medications are some of our main weapons against respiratory diseases such as asthma, bronchitis and COPD exacerbations. Once an aerosol combines with living organisms such as viruses or bacteria it becomes a bioaerosol, a process that occurs when the patient coughs, sneezes, speaks or simply breathes out.
The bad reputation aerosolized medications have received is linked to their suspension in the environment from minutes to hours depending on their size and the surrounding conditions. (1,2,8) When treating patients with aerosolized medications, up to 50% of the intended treatment is not inhaled by the patient, instead a large number of particles are released into the surrounding atmosphere. These un-inhaled aerosols are called fugitive emissions. Scientists believe that through the mechanism of bioaerosols combining with fugitive medication aerosols, COVID-19 has spread and infected others nearby. (3,4,10)
This is the main reason healthcare professionals have stopped using aerosolized medications. (5)
The particles produced by aerosolized treatments range from 1-5 microns in size, (6,8) compared to the 0.06-0.14 micron size range of the SARS-CoV-2 virus. (7) One study showed the size of fugitive emissions ranging between 0.86-1.4 microns across all nebulizer combinations. (8) Vibrating mesh nebulizers (VMN) are reported to generate smaller micron size distributions than those generated by jet nebulizers, improving medication delivery, but due to their smaller size, lighter particles are reported to remain suspended longer in in the air. (8)
Experiments with a human patient simulator have shown that significant quantities of exhaled droplets exit through the side vents of a typical facemask. (9) The risk of exposure to these exhaled droplets being accompanied by COVID-laden bioaerosols has led healthcare workers to take extra protective measures if within 0.8 meters of patients with febrile respiratory illnesses of unknown etiology, even in isolation rooms under negative pressure. (10)
The avoidance of nebulized medications—a mainstay of respiratory therapy—has made the standard treatment of shortness of breath particularly challenging during the pandemic. Some practitioners have adopted the use of breathactuated nebulizers (BANs) as a safer option since they produce less aerosols and increase the concentration of medication delivered. However, breath-actuated nebulizers do NOT reduce fugitive bioaerosols. As all respiratory therapists know, the first thing that a “tight” asthmatic or COPD patient does when bronchodilators open up their airways, is cough! Further, the work of breathing and respiratory rate are both increased due to the patient’s dyspnea, and lung compliance is decreased. The combination of dyspnea and coughing are forceful mechanisms which expel bioaerosols into the air and increase the risk to front line healthcare personnel.
Researchers have confirmed that viruses are contained in the patients’ exhaled breath. (4,11)
Our data has confirmed that use of the SafetyNeb™ can drastically reduce the presence of environmental bioaerosols during treatment.
This effectively eliminates the risk of bioaerosol-contaminated fugitive emissions to the healthcare professionals who risk their lives each and every day to treat others. This type of innovation will undoubtedly be effective for the next superbug which many experts fear will not wait another century to developOur data has confirmed that use of the SafetyNeb™ can drastically reduce the presence of environmental bioaerosols during treatment.
This effectively eliminates the risk of bioaerosol-contaminated fugitive emissions to the healthcare professionals who risk their lives each and every day to treat others. This type of innovation will undoubtedly be effective for the next superbug which many experts fear will not wait another century to develop.
As we move past the current COVID-19 pandemic into the future, medical professionals will continue to be confronted with patients presenting with cough, fever and shortness of breath due to unknown causes. Safety will always take priority, but it shouldn’t be at the expense of quality of care. A mask that can filter out over 99% of exhaled bioaerosols allows us to strike the perfect balance between safety and quality of care so we can get
back to the work we are here to do.
The author of this article pays tribute to our Frontline Workers, especially our Respiratory Therapists, EMTs and nurses for their dedication, tenacity, and bravery as they approach each patient with care and compassion despite the dangers of viral transmission. See “Lost on the Frontline”.
- Long C.M., Suh H.H., Catalano P.J., Koutrakis P. Using time-and size-resolved particulate data to quantify indoor penetration and deposition behavior. Environ. Sci. Technol. 2001;35:2089–2099. doi: 10.1021/es001477d.
- Nazaroff W.W. Indoor particle dynamics. Indoor Air. 2004;14:175–183. doi:10.1111/j.1600-0668.2004.00286.x.
- Somogyi R., Vesely A.E., Azami T., Preiss D., Fisher J., Correia J., Fowler R.A. Dispersal of respiratory droplets with open vs closed oxygen delivery masks: Implications for the transmission of severe acute respiratory syndrome. Chest. 2004;125:1155–1157. doi: 10.1378/chest.125.3.1155.
- Fabian P, McDevitt JJ, DeHaan WH. Influenza virus in human exhaled breath: an observational study. PLoS ONE. 2008;3:e2691.
- CDC Infection Control Precautions for Aerosol-Generating Procedures on Patients Who have Suspected Severe Acute Respiratory Syndrome (SARS) [(accessed on 18 August 2018)]; Available online: https://stacks.cdc.gov/view/ cdc/25034.
- ICRP Human Respiratory Tract Model for Radiological Protection. Ann. ICRP. 1994;24:1–3. doi: 10.1016/0146- 6453(94)90004-3.
- Zhu N, Zhang D, Wang W, et al. A novel coronavirus from patients with pneumonia in China, 2019. N Engl J Med. 2020;382(8):727–733. doi: 10.1056/NEJMoa2001017.
- James A. McGrath,1,* Andrew O’Sullivan,2 Gavin Bennett,2 Ciarraí O’Toole,1 Mary Joyce,2 Miriam A. Byrne,1 and Ronan MacLoughlin2 Investigation of the Quantity of Exhaled Aerosols Released into the Environment during Nebulisation Pharmaceutics. 2019 Feb; 11(2): 75.
- Hui D.S., Hall S.D., Chan M.T.V., Chow B.K., Tsou J.Y., Joynt G.M., Sullivan C.E., Sung J.J.Y. Noninvasive Positive-Pressure Ventilation: An Experimental Model to Assess Air and Particle Dispersion. Chest. 2006;130:730–740. doi: 10.1378/ chest.130.3.730.
- Hui D.S., Chow B.K., Ng S.S., Chu L.C.Y., Hall S.D., Gin T., Chan M.T.V. Exhaled Air Dispersion Distances During Noninvasive Ventilation via Different Respironics Face Masks. Chest. 2009;136:998–1005. doi: 10.1378/chest.09-0434.
- Jones RM, Brosseau LM. Aerosol transmission of infectious disease. J Occup Environ Med 2015; 57:501.
- Wittgen B.P., Kunst P.W., Perkins W.R., Lee J.K., Postmus P.E. Assessing a system to capture stray aerosol during inhalation of nebulized liposomal cisplatin. J. Aerosol Med. 2006;19:385– 391. doi: 10.1089/jam.2006.19.385.
